My Husband Had A "scope" Done Of His Stomach And

My husband had a "scope" done of his stomach and his doctor is saying it is an "Inflamed stomach" every time he sits down to eat he starts to belch and burp and is very uncomfortable. He has COPD and on the same med. for that for a very long time with no changes. My concern is he is not eating right, surviving on Jello, yogart, pudding all soft foods soups that kind of thing. Doctor gave him an antibiotic this past Monday and it doesn't seem to be working yet .........Is there something he is eating or maybe meds that can cause this?